How to repair invalid volume header error?

I connect my 3TB external hard drive to my MBP, but it failed to appear in Finder or on the Desktop. Plug out and reconnect it, nothing changes. I run Disk Utility and it finds an invalid volume header. And Disk Utility can't repair it. It can't be read or mounted. How to repair invalid volume header error? Please help!

Invalid volume header is a fairly common and relatively serious problem. Invalid volume header error can be caused by many reasons, such as forced power off, virus attack, improper operation to the Mac or hard drive. When we face the invalid volume header error, the failed hard drive can't be read or mounted, and Disk Utility may cannot repair invalid volume header error even though it proceeds "Repair Disk" successfully.

Some of us know that if Disk Utility cannot repair it, we can reformat the failed hard drive and go to our backup. But if there is no backup for the drive, we will lose all our data in that drive. By the way, any operation to the failed hard drive will cause data corruption, including "Repair Disk". On this occasion, we should recover data from invalid volume header hard drive, and then fix invalid volume header hard drive.

This article will provide us efficient Mac data recovery software to recover data from invalid volume header hard drive and tell us how to repair invalid volume header hard drive.